The present invention is directed to preventing deformation of an engine block of a motor, and in particular to a brace for mounting to an engine block to prevent deformation.
Many of the components of reciprocating motors, such as automobile, light truck, and heavy-duty motors, are subjected to high loads during operation. One such component subjected to high operational loads is the engine block or block, which experience loads from the combustion events occurring in the combustion chambers formed by the cylinder heads, pistons, and cylinder bores of the block. These forces are transmitted to the engine block at, amongst other locations, the cylinder heads and the crankshaft, which is mounted to the engine block.
A portion of the forces that are applied to the engine block are imparted in a non-linear dynamic manner due to the alternating firing sequence of the pistons and the reciprocating connection of the connecting rods to the pistons and crankshaft. These forces impart strain on the engine block, which results in distortion and can even lead to failure of the engine block.
Various locations on the engine block will be subjected to distortion from twisting, compressive, and/or tensional forces. The cylinder bores are one such area subject to distortional strains, with this area experiencing significant distortion due to their proximity to the origin of the forces and the relatively narrow walls of the cylinder bores.
Distortion to the cylinder bores can be very problematic to the operation of reciprocating motors. For example, during the compression cycle of the piston distortion to the cylinder bore can reduce the amount of compression in the cylinder by allowing the gas and air mixture to escape past the piston rings, thus reducing the amount of gas and air in the cylinder prior to firing. Furthermore, upon a combustion event, the burnt gasses can escape past the piston rings and reduce the force transmitted to the crankshaft, thus further reducing the power output of the motor. In addition, such distortion can improperly allow the discharging of combustion exhaust gasses into the oil pan area, and allow oil to enter the combustion chamber and increase harmful emissions. Distortion to the engine block cylinder bores, therefore, reduces the efficiency of a reciprocating motor as measured by the amount of fuel consumed relative to the power output, thus necessitating that the motor utilize more fuel to obtain a desired power output than would otherwise be required, and can increase harmful emissions.
Distortion to the engine block can also result in total failure of the motor due to cracking of the block or can cause the piston to seize in the cylinder bore due to an excessively out of round condition of the bore. Engine blocks are most commonly constructed of cast iron, but may alternatively be constructed from aluminum, or other alloys or materials, and are relatively inelastic. Therefore, strain causing distortion can cause cracks to form in engine blocks, particularly at sharp corners or areas having thinner wall sections or at voids formed during the casting operation. The cyclic nature of the strain can cause the cracks to propagate and cause the motor to fail.
Distortion of engine blocks is a problem for all motors, whether spark ignition (SI) gasoline motors or combustion ignition (CI) diesel motors or alternative fuel burning motors. However, engine blocks formed to have a V-style configuration are particularly apt to experience distortion causing strain. V-style motors are formed to have two cylinder banks that are oriented at an angle with respect to one another and are produced in a wide variety of sizes, such as V6 and V8. V-style motors are used for SI, CI, or alternative fuel burning motors. In general, each bank of cylinders of a V-style motor extends out away from a central portion of the block and there typically exists an upper valley between the cylinder banks. The upper valley usually contains components related to actuating the engine valves and is thus referred to as a lifter valley and an intake manifold may be placed above the upper valley.
The non-linear forces resulting from the offset relationship of the pistons firing within the angled cylinder banks and the extension of the cylinder banks from the central portion of the engine block contribute to the strain causing distortion in this area of an engine block. These strains are magnified on engines subjected to high loads, such as towing vehicles or racing vehicles, but are also significant relative to the continuous drive to obtain more performance from smaller engines where the lighter weight engine blocks are constructed of less material and thus subject to higher strains.
Devices have been constructed to attempt to reduce engine block strain. For example, U.S. Pat. No. 6,928,974 issued to Markou discloses a reinforcement plate for a reciprocating engine, also known as an engine girdle, constructed for attachment to the lower portion of an engine block. However, the disclosed reinforcement plate does not provide reinforcement to the upper portion of the engine block adjacent the cylinder bores.
Therefore, a technique for reducing engine block deformation at the upper portion of V-styled motors is desired in order to increase efficiency and reduce engine block failures.